从零开始学android小示例程序

    <Button
        android:id="@+id/GreenBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/showWord"
        android:layout_marginLeft="22dp"
        android:layout_marginTop="28dp"
        android:gravity="left|center_vertical|center_horizontal"
        android:text="@string/GreenBtnText" />

    <Button
        android:id="@+id/BlueBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/YellowBtn"
        android:layout_alignBottom="@+id/YellowBtn"
        android:layout_toRightOf="@+id/YellowBtn"
        android:gravity="left|center_vertical|center_horizontal"
        android:text="@string/BlueBtnText" />

    <Button
        android:id="@+id/YellowBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/GreenBtn"
        android:layout_alignBottom="@+id/GreenBtn"
        android:layout_toRightOf="@+id/GreenBtn"
        android:gravity="left|center_vertical|center_horizontal"
        android:text="@string/YellowBtnText" />

</RelativeLayout>

 

 

复制代码
package com.example.demo1;
import android.os.Bundle;